Resident Fantasy Genius

Avoiding the Late-Season Ratio Trap

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If your league’s annual trade deadline hasn’t already passed, it’s likely that today or tomorrow will be the last day to make deals. The remainder of my leagues’ deadlines will all pass within the next 48 hours, and I know that I’ll be in contact with almost every owner in the league in that time (if I haven’t already begun talks) to see what they’re looking to acquire, what they’re looking to deal, and how that fits with what I’m trying to do. Today, I wanted to pass along one piece of advice that might be useful to you in your own dealings: be very careful when trying to move the needle on your ratios.

With five of six months very nearly in the books, it will be incredibly difficult to budge most ratios more than a few points. Of course all situations are different and need to be evaluated independently, but this is a general rule that applies to nearly all fantasy teams at this time of year. As a result, while that deal you have on the table for Clayton Kershaw may seem really appealing, it’s important to do your homework and make sure such an acquisition is truly going to have the desired effect.

Let’s run some sample numbers to see what I’m talking about. At this point in the year, a typical fantasy staff might have logged 1000 innings with a 3.60 ERA and 1.23 WHIP (these are the averages from my only mixed league this year, which should be close enough for our purposes today; naturally, your mileage may vary). Now let’s say we want to add Kershaw to the staff. To figure out his impact on the team’s end-of-season ERA and WHIP, we’ll add up three things:

1. The team’s performance to date

2. Kershaw’s rest of season projection

3. The assumption that the team will perform the same as it has been over the final month of the season, multiplied by eight-ninths, since we have to exclude the spot Kershaw will occupy*

*This is done for the sake of simplicity. Naturally, if you’re running these calculations yourself, you’ll want to factor in the projections for each individual player on your team.

In our hypothetical example, we can see just how little impact even an absolute stud like Kershaw will have on the team. He’ll lower its ERA by just 0.03 points and its WHIP by 0.005 points. And if you think about, it makes sense: Kershaw’s PECOTA-projected 49 innings over the rest of the season would make up just 4 percent of the team’s end-of-season total. How much impact can we really expect that to have?

This isn’t necessarily meant to discourage you from trading for Kershaw, just help you set realistic expectations. If ERA isn’t going to be a photo finish, you may be better off trading for a player who can help in a category that will be close.

Knowing all this can open up some interesting strategic doors. If you find yourself in a comfortable enough position, knowing how little your ratios will budge at this point in the season could give you the flexibility to employ an “all crappy starter” strategy, or at least a watered-down version of such an approach. Obviously multiple pitchers with extreme (good or bad) ERAs and WHIPs will have a greater impact on your team’s total than a single Kershaw, but if you have enough wiggle room, you might want to consider trading your top starters for offensive help and plugging in crappy starters to hold up your strikeouts and chase wins (yes, I’m okay breaking the “cardinal rule” of fantasy baseball by chasing wins—more about this on Monday). This is essentially what I’ve done in Tout Wars. There’s no shame in rocking Fernando Abad and Casey Kelly as your third and fourth starters (okay, maybe a little). Just make sure you’re running the numbers and know exactly what you’re getting yourself into.

Question: at what point do the PFM dollar values stop approximating a useful prediction of next year's dollar values for "regular" (non-injured, starting, non-scenery changing) players?

As in, if in my league projections through the end of this season, Ryan Braun is worth $42 in the remained of this year, is his April 1st 2013 projected dollar value within $2 either way?

Could this be run on previous seasons to determine whether or not the "end-of-year" PFM dollar values are useful in keeper auction leagues for deciding which players to trade for in the offseason prior to a new PFM release?